How do you slove this problem in this image?

Ex1) a. supplementary (angle A + angle B gives 180) b. neither c. complementary (angle A + angle B gives 90)

Ex2) An angle of 180° (since it makes a straight line)

Supplementary angles are any angles that give 180 in sum, so for example 90° and 9°

Two different ones could be 150 and 30, for example

2 complementary angles are any angles that give 90 in sum, so for example 45 and 45 or 50 and 40

Since we know that a straight angle is 180 (like in the picture), and we are given (in that straight angle) an angle of 90° (the left) and 55° (CED) we only need to find BEC. Again, since a straight angle gives 180°, we just need to sum all of these and get 180°:

90 + 55 + BEC = 180
145 + BEC = 180
BEC = 180 - 145
BEC = 35°